Explanation 3:
Choice A contains a related word. You might have associated the word "letter" with "type".
Choice C contains another distractor called a homonym. A homonym is a word that sounds the same but is spelled differently. On the real test you will not be able to read the answer choices. You have to be able to understand which word is which by the context. In this case the homonyms are "fax" and "facts". In the question, "fax" is a verb. In the answer choice it is a noun. You should make a list of all of the homonyms you come across.
Other homonyms
week/weak
add/ad
hear/here
knot/not
right/write
weight/wait
The correct answer is B.
Transcript:
Did you fax the letter to the client?
A) I'll type it after lunch.
B) No, I sent it by email.
C) I collected some important facts.